1. Field of the Invention
The invention pertains to horizontal coke oven batteries generally and, more particularly, to apparatus for one-spot catching, transporting and quenching of hot coke after it is pushed from a chamber of a horizontal coke oven battery.
2. Description of the Prior Art
A horizontal coke oven battery is comprised of a series of side-by-side coking chambers that extend transversely from the common longitudinal line of the battery. Coke that is produced in the coke oven battery is discharged from each coking chamber at the coke side of the battery. Conventionally, tracks extend parallel with and adjacent to the coke side of the battery. A coke receiving car runs along these tracks. The coke receiving car is positioned below the level of the coke ovens.
In a conventional coke oven operation, the coke receiving car is located adjacent the coke side of the particular oven to be discharged. Interposed between the open coke oven and the coke receiving car is a coke guide, the purpose of which is to direct the discharging coke into the coke receiving car. Concurrent with the commencement of the discharge of coke, the coke receiving car is drawn slowly past the coke guide, the object being to evenly distribute the coke within the coke receiving car. The full charge of a single coke oven is discharged into the coke receiving car which is then transported to a quenching station where a large volume of water is sprayed from overhead onto the hot incandescent coke to cool it. From the quenching station, the coke receiving car is transported to a coke wharf whereon the quenched coke is dumped.
The conventional coke receiving car has an open gondola-style hopper with a bottom sloped away from the coke oven battery and toward the coke wharf. The side of the hopper adjacent the lowest point of the sloped bottom has dump gates mounted thereto which can be pivoted open to dump the coke.
In operation, one end of the hopper of the coke receiving car is positioned adjacent to, but just below, the discharge end of the coke guide. A signal is sent to the pusher machine operator on the opposite side (pusher side) of the coke oven battery. A common means of signalling utilizes the whistle of the locomotive which is used to move the coke receiving car. At the signal, the push commences and the incandescent coke begins to gravitate through the coke guide down into the open hopper. Concurrently, the locomotive operator causes the locomotive to begin slowly moving the gondola past the coke guide point of coke discharge. Thus the coke becomes more or less evenly spread in the hopper.
The even spreading of the coke within the hopper is important to the quenching operation. Once the coke receiving car has received the full contents of the coke oven, it is moved by the locomotive to a quenching station. The object of the quenching operation is to, as rapidly as possible, cool the coke to a temperature below its oxidation point. However, it cannot be cooled below a point at which the heat of the coke will not rapidly evaporate the residual moisture to dry the coke. If the coke is uneven within the hopper, either those portions of the pile which are deeper will not be sufficiently cooled or those portions of the pile which are shallow will be cooled too much. The result is inconsistent coke quality, the coke being either too oxidized or containing too much moisture.
The quenching operation comprises spraying a given volume of water onto the incandescent coke within a certain period of time. As a rule of thumb, approximately 500 gallons of water are used to quench each ton of coke and the quenching operation is performed in a time period of approximately 30 to 90 seconds.
After the coke has been quenched, the coke receiving car is moved to a coke wharf by the locomotive. A conventional coke wharf is in the form of an inclined plane, positioned to form an extension of the sloped floor of the hopper of the coke receiving car. To discharge the coke onto the coke wharf, simply, doors or gates in the side of the hopper, adjacent the coke wharf, are opened and the coke rolls out onto and down the incline of the coke wharf.
Enter the environmentalists who perceived, among other things, that the before described operations cause large quantities of pollutants, in the form of noxious gases and particulate matter, to be expelled into the atmosphere. A hue and cry was raised which persuaded legislative bodies to propound regulations which mandate that coke battery operators cease and desist from so polluting the atmosphere. The only problem was, and still is, a mere question of how.
Initially, the developments in the area of control of pollution emanating from coke discharge and quenching operations were directed at enclosing the whole operation. Large shed-like structures were built to cover the whole coke side of coke oven batteries. Ventilation and pollution control equipment were built into the enclosures. Experimentation proved that although the pollution problem was abated to some degree, the enclosure system could not eliminate the pollution to the degree required by regulation. And further, the enclosure system proved to be extremely costly both in terms of capital expenditure and in terms of operation.
The second order of approach to eliminating the pollution problem was, generally, to enclose the passageway that the coke traveled through on its way from the oven into the coke receiving car and to enclose, or screen, the hopper of the coke receiving car, the idea being to contain the emanating noxious gases and particulate matter, at least until the coke receiving car was moved to the quenching station. An example of this approach to solving the problem is found in U.S. Pat. No. 3,984,289, issued to Sustarsic et al. on Oct. 5, 1976. The disclosure of this patent, however, still contemplates the movement of a conventionally sized quench car and hopper, slowly, past the coke guide.
A third order of approach to eliminating the pollution problem was to stationarily position, or spot, the coke receiving car, rather than slowly moving it, during the discharge of coke from the coke oven. Pollution control equipment was generally the same as that found in U.S. Pat. No. 3,984,289. An example of a system utilizing this type of "one-spot" coke receiving car is found in U.S. Pat. No. 3,868,309 issued to Sustarsic et al. on Feb. 25, 1975. Thus began the evolution of the one-spot coke quench car concept. The great distinguishing advantage of the one-spot concept was recognized to be that it eliminated the need for a moving seal on the gondola or hopper of the one-spot car. The seals could be stationarily fixed into position prior to the discharge of coke, making a much tighter seal design possible. A slowly moving car requires a continuously moving seal which, in turn, requires a looser fit of the seal; the result is a less effective seal in terms of containing pollution. The distinction is further described in application Ser. No. 846,892 filed Oct. 31, 1977, by Becker, Jr. et al. along with the problems inherent in the one-spot quench car concept.
The prior art in the field of cylindrical or rotary quench cars is outlined in application Ser. No. 785,366 filed Apr. 7, 1977 by Cain et al., as well as the application of a rotating cylindrical concept to one-spot coke quench cars. The present application is a continuation-in-part of that application.
The critical factors which are necessary to distinguish a one-spot quench car as technologically and commercially viable are twofold. The car must be capable of eliminating the discharge of noxious gases and particulate matter into the ambient atmosphere. And the car must lend itself to satisfactory quenching of the incandescent coke therein. These factors are added to the basic requirements of all coke receiving cars, that is, the ability to contain the full volume of coke discharged from a coke oven, the ability to transport the coke to the quench station and then the coke wharf, and the ability to discharge the coke onto that coke wharf.
Those skilled in the art will recognize that when a coke receiving car is stationarily spotted adjacent a coke guide, the oven volume of coke discharged into the hopper of that car will naturally pile up to form a mound. To contain this mound, the hopper must be deeper. But the mound itself is of unequal depth as measured vertically at different points. And the average depth of the mound is much greater than the shallow depth of coke that is spread in a conventional coke car which is slowly drawn before the coke guide during the coke discharge.
Conventionally, the coke is quenched by spraying water onto the shallow layer of coke which is fairly evenly spread in a conventional coke receiving car. Those skilled in the art have heretofore assumed that identical quenching methods could be satisfactory when applied to a relatively deep mound of coke piled in a one-spot quench car. Such has not proven to be the case. The application of conventional quenching methods to mounded coke in one-spot quench cars has produced either a coke that is adequately quenched, coming from the mound surface, with highly oxidized coke from the interior of the mound; or coke that is over-cooled, containing a too high moisture content, coming from the interior of the mound. Generally, the quality of the coke produced by such a method is inconsistant in oxidation and water content and not of uniform size.
A partial solution to the problem is to level the coke within the hopper, thus producing a more even depth. But the coke still remains at a much greater depth than the shallow spread coke of conventional coke receiving cars. Means are needed to concurrently quench both the interior of the coke pile and the surface.